Oil burning apparatus



Sept 17. 1940. J. L. OBRIEN on. BURNING APPARATUS Filed July 9, 1938 2 Sheets-Sheet l mvigglz ATTORNEY P J. 1... OBRIEN 2,215,272

OIL BURNING APPARATU$ Filed July 9, 1938 2 Sheets-Sheet 2 LNVENTORI 1a I TTOR EY Patented Sept. 17, 1940 UNITED STATES .OIL BURNING APPARATUS James L. O'Brien, Cleveland, Ohio, assignor to Cleveland Steel Products Corp., Cleveland, Ohio,

a corporation of Ohio Application July 9, 1938, Serial No. 218,403

1 Claim.

This invention relates to oil burning apparatus and more particularly to oil burning apparatus of the pressure atomization type.

One of the objects of the present invention 1 is to provide an oil burning apparatus of the pressure atomization type of such new and improved design that the air entering the blast tube is caused to spiral and violently whirl against the inside wall thereof to insure highly efllcient delivery of combustion supporting air and to provide for an exceedingly quiet fire.

Another object is to provide an oil burning apparatus of the pressure atomization type with a blast tube of such improved design as to accel- 15 erate velocity of and to effect placement of the combustion supporting air in such shape and location as to cause intimate mixing of the air and oil streams at the point of discharge from the blast tube.

20 Another object is to provide means in an oil burning apparatus of the pressure atomization type to retard deceleration of the combustion supporting air throughout the coasting period of the fan on shut down whereby to minimize 25 vibrations and pulsations which frequently occur in conventional oil burners.

Another object is to provide means whereby movement of the combustion supporting air through the center of the blast tube is negligible whereby the atomized oil issuing from the burner nozzle is enveloped in a rotating cone of air.

Another object is to provide an oil burner of compact arrangement in which all parts thereof can be easily assembled or removed from the 85 assembly.

A further object is to provide an oil burner of the pressure atomization type with new and improved means for'easily assembling and con- .necting the electric ignition electrodes with the 40 ignition transformer entirely within, the burner structure whereby to eliminate wiring connections exteriorly of the burner assembly.

With the above and other objects in view, the present invention consists in certain features of 45 construction and combination of parts to be hereinafter described with reference to the accompanying drawings and then claimed. In the drawings which. illustrate suitable embodiments of the invention; 50 Figure 1 is a front end view of the oil burning apparatus looking toward the burner nozzle and.

blast tube discharge end.

Figure 2 is a side view of the burner shown in Figure 1.

66 Figure 3 is an enlarged longitudinal section of the burner taken approximately on the line 33 of Figure 1.

Figure 4 is. a transverse section of the blast tube taken approximately on the line 4-4 of Figure 3.

Figure 5 is a transverse section taken approximately on the line 55 of Figure 3.

Figure 6 is an enlarged fragmentary side elevation of the burner.

Figure 7 is a fragmentary transverse section [0 taken approximately on the line l-I of Figure 6, and

Figure 8 is an enlarged plan view of the electrode and burner nozzle and oil tube assembly.

Referring to the accompanying drawings in which like numerals refer to like parts throughout the several views, the oil burner apparatus shown in the embodiment of the present invention, includes a casing Ill having a fan chamber ii, and a plenum chamber I2 provided by spaced :0 front and rear walls i3 and i4, respectively, and a continuous connecting wall l5, of the casing i0. 'I'he casing I0 is providedwith an air outlet IS in its front wall l3 through which air from the plenum chamber i 2 is discharged. Secured as to the frontwall i3 coaxial with the outlet i6 is. a blast tube llfthe blast tube being provided at its discharge end with an air diffuser l8 having overlapping spiral vanes ID.

The burner is supported on adjustable supports 80 connected with the casing ill and blast tube I1.

Secured to the rear wall i4 of the casing i0 is an electric motor 2i .having its shaft 22 extending into the fan chamber ii and carrying-s5 a fan 23 of the peripherally bladed type.

The casing in has an air inlet 24 through the front wall I 3 substantially coaxial with the fan 23, and adjacent this inlet is an air inlet chamber 25 defined by a cylindrical wall 26 having 4 inlet apertures 21 therein which 'are adjustable in size by means of an adjustable apertured band 28 surrounding the wall 2 Secured to the side of the inlet chamber 25 is an oil pressure pump 29 having its shaft 3! extending through the inlet chamber and connected at II with the motor shaft 22.

The pump outlet isconnected by means of an oil conduit 32, extending through the blast tube IT, with the rear end of the oil supply tube 33, which has a nozzle 34 at its front end. The oil supply tube 33 is supported on a bracket 35 having a threaded portion 36 extending through an elongated opening 31 in the bottom portion of the blast tube ii, a nut ll being provided to adjustably secure the bracket 35 to the blast tube H. The front end of the tube 33, adjacent the nozzle 34, is additionally supported by a three legged bracket 39, the legs of which have slidable engagement with the inside wall of the blast tube l'l.

Secured to the rear wall [4 adjacent the plenum chamber I2 is an ignition transformer 40 V tapering reduction in diameter from the inlet end having an electrical connection with a pair of tubular contact elements 4|, parallel to the axis of the blast tube, each of which is mounted within a tubular insulator 42. The insulators 42 are mounted within an opening 43 in the rear wall I4 of the casing I0.

Secured to the bracket 35 by means of a clamp 44 are a pair of ignition electrodes 45 and secured to the electrodes are rigid longitudinally extending connectors 46, the free ends of which have sliding engagement within the contact elements.

The blast tube [1 is provided at one side with an assembly opening 41 through which the oil supply tube and electrode assembly is inserted In doing this the assembly is merely inserted longitudinally through the opening 41 until the rigid connectors 46 are within the same and then moved rearwardly to slide the connectors 46 within the contact elements 4|, after which the threaded portion 36 is inserted through the elongated opening 31, then the assembly is moved longitudinally to adjust the nozzle position with respect to the air diffuser, and finally the nut 38 is threaded on the portion 35 and tightened. The opening 41 is normally closed by means of a cover plate 48 secured to the blast tube ll.

Referring to Figures 5 and 7, it will be noted that the connecting wall 15 of the casing I is of curvilinear shape except for one side portion lfia, it having curvilinear upper and lower end portions I51) and IE0, respectively, which at the side opposite the straight side portion I50. continue and join with each other at that side of the plane passing through the axes of the air outlet and inlet openings l6 and 24, respectively, nearest the wall portion la but spacedtherefrom to provide a communicating passageway 49 between the fan and plenum chambers H and I2, respectively.

In order to impart and insure a violent spiral action to the air entering the blast tube through the plenum chamber outlet IS, the connecting wall substantially throughout the curvilinear extent thereof defining the plenum chamber l2 inclines'from the front wall [3 toward the rear wall I4 and inwardly toward the axis of the plenum chamber, as shown in Figures 3, 5 and 7.

Preferably, the angle of inclination is not constant but is at a maximum opposite that portion lid of the connecting wall which separates the fan and plenum chambers and progressively decreases to a minimum at such portion I511. The air enters the plenum chamber i2 through the passageway 49, as shown by the arrow in Figure 5, in a straight line path and strikes the curvilinear end portion and follows around the same and there passes through the outlet I6 into the blast tube I'l.

It is to be noted that the blast tube H has a toward the outlet end thereof.

In operation, the combustion supporting air is given a spiral movement by the curvilinear wall of the plenum chamber which air is caused by the inclination of this wall outwardly toward the inlet end of the blast tube to enter the blasttube more at the inside wall than at the center thereof and to flow through the blast tube in a spiral path with a maximum velocity at the inside wall, the air movement through the center of the blast tube being practically negligible. The gradually tapering inside wall of the blast tube gradually accelerates the air velocity and the spiralling action is'further increased by the spirally vaned difiuser at the discharge end, whereby the atomized oil discharging from the burner nozzle is enveloped in a rapidly whirling or rotating cone of air of accelerated velocity at the region where the oil and air are first brought together, instead of being carried out toward the back wall of the combustion chamber by a high velocity air stream emanating from the center of the blast tube as in conventional burners of the pressure atomization type. As a result, there ensues an intimate mixing of the atomized oil and combustion supporting air at the immediate region of discharge from the blast tube, and combustion is practically completed before impact against the back wall of the combustion chamber.v

Another advantage is that throughout the coasting period of the fan, the tapering blast tube retards deceleration of the combustion supporting air, thereby allowing for complete combustion of the oil draining from the oil conduit extending from the pump to the nozzle during this period.

A further advantage is that the objectionable vibrations and pulsations, which frequently occur in conventionally shaped blast tubes which seek to control velocity and air placement with the use of diifusers, baiiles, etc., is minimized.

The particular manner of air flow and discharge tends to materially increase the efficiency.

of operation and to materially aid in providing a quiet fire.

In order to provide for a balanced external appearance, it will be noted that a wall portion lie parallel to the portion lie is provided which forms a space 50. A conduit Sla containing the transformer wires for the motor and the ignition transformer is secured to an opening 5| in the front wall l3 through which the wires extend and are provided with connectors 52 within the space, 50 to which the motor leads 53 extending through an opening 54 in the rear wall l4, and the transformer leads 55 extending through an opening 56 in the wall I 4, are connected.

An opening 5 in the wall portion lie is provided for access to the connectors 52, which opening is normally closed by a cover plate '58.

It is to be understood that various modifications of the structure shown and described may be made without departing from the scope of the appended claim.

What I claim is:

In an oil burner of the pressure atomization type having a fan housing provided with an air,

inlet and an air outlet, a motor driven fan within said housing and forcing combustion supportoperation of said fan and fuel pump, deceleration of the air velocity will be retarded during the coasting period of said fan to support combustion of the oil draining from said nozzle, said housing having an air deflecting wall of curvilinear shape adjacent said outlet and extending longitudinally with respect to the axis of said blast tube for causing the air to spiral through said blast tube with greater velocity adjacent the wall thereof than at the center region thereof,

whereby upon cessation of operation of said fan and fuel pump, the air due to its spiral movement and the retardation of the deceleration of its velocity will support combustion of the oil draining from said nozzle during the coasting period of said fan.

' JAMES L. O'BRIEN. 

